My name is Dale.
It sort of sounds like the front and rear axle assemblies are not really totally matched. It could be different brand or tire size ( fronts to back) or problems with the posi-traction, if so equipped.
I would mark each tire with chalk with the vehicle on a flat concrete surface and then raise the front or back and see how much wind up is being loaded in the system.
You are right on to be concerned about this condition or symptom because it can really accelerate wear and or snap part of the drive train if you do not find out the cause.
Let me know what you find with the wind up and then we can go from there.
Have a Blessed Day,
This is a little hard to explain and I could be completely off base here, but if the front or rear total circumference of the tires is not exactly the same for what ever reason, when the Jeep is rolling down a paved road inXXXXXthe front or rear differential can get ahead or behind the other differential and create what I call a "wind up" situation that applies pressure between the two differentials. I have seen this more than once where you pick up the front or the back and the tires will spin a 1/4 to 1/2 turn to unload the pressure. Even if it is not inXXXXXbut you have posi-traction or limited slip differentials this can happen side to side as well.
I just think you need to mark the tires and check to see of the differentials are all running in sync with each other or whether one side or from front to back are loading up or winding up pressure when it is rolling.
It may not be your problem but it is easy to check before you get to deep into other internal problems that can cause this condition.
Thank you for doing the test. I just want to avoid going (researching) internally deeper until I knew for sure that it was not an external problem.
Did they move when you pick up one end or the other? From what you are saying the tires (the marks) at all 4 points stayed exactly where they were when the vehicle was sitting on the ground. If that is in fact so then I would say that the clutches in either the front or back (or both) of the posi-traction or limited slip are either glazed or worn. Sometimes this can be eliminated by changing the gear oil and adding a clutch de-glazer.
How many miles do you have on your Jeep Cherokee? What year is it, so I can go into the database and take a look at the set up?
Let me the details so I can look for you.
Sorry about the delay. There was a computer problem that would not let me access your file so I could not reply back. The drive shafts are usually indexed to keep them in balance. How do the the U-Joints themselves look? A bad U-Joint will generally clunk or make a popping sound. The indexing is done via the spines to line the crosses up so they are at 90 degrees from each other.
I hope that helps you.
I found some information about your drive shafts. I think there may be a problem with the adjustments. Take a LOOK and see if this helps:
Jeep vehicles may come equipped with one of two different type front driveshafts. Type one has a conventional universal joint at the axle, but a double offset joint at the transfer case. Type two has a conventional universal joint at the axle and a double cardan joint at the transfer case.
Front driveshafts on 1984 vehicles use the type one universal joint only. Front driveshafts on 1985-98 vehicles use either type one or type two.
Type one driveshaft
Type two driveshaft
Before removing a driveshaft, always matchmark it at the U-joints so that it can be reassembled in the same manner
Removal of the front drive shaft U-joint strap bolts at the transfer case side
After removing the U-joint strap bolts and straps, hold onto the joint at the needle bearing caps so that they cannot fall apart
Matchmark the shaft ends, axle and transfer case.
Remove the U-joint strap bolts at the front axle yoke.
If equipped with a double offset U-joint, remove the double offset joint flange nuts at the transfer case.
If equipped with a double cardan U-joint, remove the double cardan joint flange nuts at the transfer case.
Installation is the reverse of removal. Install new strap bolts and tighten strap bolts to 14 ft. lbs. (19 Nm).
Two different driveshafts are used on these vehicles. With Command-Trac®, the driveshaft has welded yokes at each end. With Selec-Trac®, a welded yoke is used at the rear and a splined slip yoke is used at the front.
Two types of rear driveshafts used
Removal of the rear drive shaft U-joint strap bolts at the differential housing side
Carefully remove the drive shaft by lowering it from the vehicle
After removing the drive shaft, install a transmission plug into the tailshaft opening so that transmission fluid will not escape
Raise and support the vehicle on jackstands.
Place the transmission in N.
Matchmark the yokes and flanges.
On vehicles with Command-Trac®, the driveshaft may be removed by disconnecting it at the axle and sliding it from the front yoke, leaving the front yoke attached to the transfer case. If you do this, however, you MUST matchmark the driveshaft and front yoke BEFORE separation.
On vehicles with Selec-Trac®, disconnect the yokes from the axle and transfer case. Remove the driveshaft.
Installation is the reverse of removal. Install new strap bolts and tighten strap bolts to 170 inch lbs. (19 Nm).